vv. 12-14 Onesimus had so endeared himself to Paul that his departure was an extremely painful prospect for the apostle. Paul could have justified keeping the slave with him, but he judged that Onesimus' obligation to return to his owner was more important. Furthermore, Paul did not really have authority over the slave; that rested with his master. If Paul had kept Onesimus with him, Philemon would have felt obligated by his regard for Paul to let his slave stay with the apostle. The service Paul probably had in mind for Onesimus was to proclaim the gospel, not to perform menial prison duties for Paul.26Nevertheless, Paul wanted Philemon to respond to his slave freely.
"The principle of consideration for others here manifested by Paul is a factor of vital importance today for effective Christian leadership. Many are the difficulties which might be avoided if those in places of authority in Christian work would follow Paul's example in this."27
"In the eastern part of the Roman Empire [including Asia Minor] during this period, fugitive slaves who sought sanctuary in a household were likely to be given temporary protection by the householder until either a reconciliation with the master had been effected or else the slave had been put up for sale in the market and the resulting price paid to the owner . . ."28
vv. 15-16 Paul suggested that God may have permitted the events that had taken place to result in greater good (Rom. 8:28), and he urged Philemon to view them in that light. The master should now regard his slave not as a slave but as a brother in Christ, which he was.29This does not mean that he would necessarily give Onesimus his freedom, though he might, but that he would treat him lovingly at least.30In Onesimus Philemon would receive one with whom he could share the fellowship of Christ and one who would render him more conscientious service than he could expect from a non-Christian.
"The supreme work of Christianity is to transform men, so that out of their transformed lives shall come the transformation of all social conditions, and the victories of righteousness and of love."31
"The principles of the gospel worked into the conscience of a nation destroy slavery."32
"Christianity is not out to help a man to escape his past and to run away from it; it is out to enable a man to face his past and to rise above it."33
"It is quite clear that in this letter Paul is not really dealing with the question of slavery as such or the resolution of a particular instance of slavery. In this verse, at least, he treats the question of brotherly love. Although Onesimus' earthly freedom may be of positive value, in the last analysis it is of no ultimate significance to him as a Christian as to whether he is slave or free. Finally what matters is to have accepted God's call and to follow him . . ."34
